[PATCH] gas: Silence GCC 10 warning tc-vax.c

[H.J. Lu]

On Wed, May 27, 2020 at 8:54 AM Martin Sebor <msebor@gmail.com> wrote:
>
> On 5/26/20 8:41 AM, H.J. Lu via Binutils wrote:
> >       PR gas/26044
> >       * config/tc-vax.c (md_estimate_size_before_relax): Replace
> >       fragP->fr_literal with &fragP->fr_literal[0].
> >       (md_convert_frag): Likewise.
> > ---
> >   gas/ChangeLog       | 7 +++++++
> >   gas/config/tc-vax.c | 4 ++--
> >   2 files changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/gas/ChangeLog b/gas/ChangeLog
> > index 052d180398..980a84f6cf 100644
> > --- a/gas/ChangeLog
> > +++ b/gas/ChangeLog
> > @@ -1,3 +1,10 @@
> > +2020-05-26  H.J. Lu  <hongjiu.lu@intel.com>
> > +
> > +     PR gas/26044
> > +     * config/tc-vax.c (md_estimate_size_before_relax): Replace
> > +     fragP->fr_literal with &fragP->fr_literal[0].
> > +     (md_convert_frag): Likewise.
> > +
> >   2020-05-26  H.J. Lu  <hongjiu.lu@intel.com>
> >
> >       PR gas/26044
> > diff --git a/gas/config/tc-vax.c b/gas/config/tc-vax.c
> > index 5634566945..f606c157bc 100644
> > --- a/gas/config/tc-vax.c
> > +++ b/gas/config/tc-vax.c
> > @@ -381,7 +381,7 @@ md_estimate_size_before_relax (fragS *fragP, segT segment)
> >         int old_fr_fix;
> >
> >         old_fr_fix = fragP->fr_fix;
> > -       p = fragP->fr_literal + old_fr_fix;
> > +       p = &fragP->fr_literal[0] + old_fr_fix;
>
> For what it's worth, I'd expect the following to suppress the warning
> as well without overly obfuscating the code:
>
>    p = &fragP->fr_literal[old_fr_fix];

It is equivalent to

p = &fragP->fr_literal[0] + old_fr_fix;

> Either way, although I intend to suppress the warning in GCC for this
> case, the GCC manual discourages using trailing arrays of non-zero
> size as flexible array members, in favor of either the C99 feature
> itself or the zero-length array extension (see Zero-Length.html).
> If it's not overly disruptive I would suggest to consider adjusting
> those accordingly.
>

GCC 10 should work on binutils 2.34, which can't be changed.

-- 
H.J.